Allelopathic Effects of Spermacoce hispida L. on Arachis hypogaea L. under In Vitro and Pot Conditions

Abstract

The study was conducted during January to April, 2023 in the Department of Botany at Government Arts College (Autonomous), Salem-7, Tamil Nadu, India,  aimed to investigate the interaction between the crop (groundnut) and the weed nattaichuri (Spermacoce hispida L.) in two different culture conditions: in vitro and pot culture. Groundnut (Arachis hypogaea L.),an important pulse crop with high protein content, used for edible purposes and to extract cooking oil. Nattaichuri (Spermacoce hispida L.), a common weed found in groundnut fields in Salem District. 10 g of leaf and stem powder separately extracted with 100 ml distilled water and considered as 100% extract. The extracts (both leaf and stem) were diluted and then tested at various concentrations (25%, 50%, 75% and 100%) for their effects on germination and growth of groundnut using distilled water as control. In the control, 100% seed germination was observed on 2^nd and 5^th day of seed sowing, but in the stem and leaf extract treatments, seed germination decreased with higher extract concentrations. In pot culture, 20% seed germination was observed with 100% leaf extract, whereas in control and other treatments, with stem and leaf extracts, 100% seed germination was recorded. Seedlings treated with stem and leaf extracts showed an increase in the growth of shoot and root, as well as the fresh weight and dry weight, than the control in the pots. The study reported two different interactions between the crop and the weed under different conditions. In in vitro culture, the allelopathic interaction was inhibitory, while in pot culture, the interaction was stimulatory.